Synergistically UV-photoprotecting sunscreen compositions comprising camphorsulfonic acid/benzophenone compounds

ABSTRACT

Topically applicable cosmetic/dermatological sunscreen compositions well suited for the enhanced UV-photoprotection of human skin and/or hair, contain synergistically SPF-enhancing amounts of (a) benzene-1,4-di(3-methylidene-10-camphorsulfonic acid), optionally in partially or completely neutralized state, and (b) at least one amino-substituted 2-hydroxybenzophenone compound having the following structural formula (I):  
                 
 
     formulated into (c) a topically applicable, cosmetically/dermatologically acceptable vehicle, diluent or carrier therefor.

CROSS-REFERENCE TO PRIORITY APPLICATION

[0001] This application claims priority under 35 U.S.C. §119 of FR-01/15861, filed Dec. 7, 2001, hereby expressly incorporated by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Technical Field of the Invention

[0003] The present invention relates to novel topically applicable cosmetic/dermatological sunscreen compositions well suited for the photoprotection of the skin and/or hair against the damaging effects of ultraviolet radiation (hereinafter referred to more simply as antisun or sunscreen compositions).

[0004] This invention more particularly relates to antisun/sunscreen compositions comprising intimate admixture of at least two specific UV-screening agents, namely, first, benzene-1,4-di(3-methylidene-10-camphorsulfonic acid) and, secondly, a specific amino-substituted 2-hydroxy-benzophenone compound, formulated into a topically applicable, cosmetically/dermatologically acceptable vehicle, diluent or carrier therefor. The combination of these two UV-screening agents provides synergistic results with regard to the sun protection factors (SPFs) conferred.

[0005] 2. Description of the Prior Art

[0006] It is known to this art that light radiation with wavelengths of from 280 nm to 400 nm permits browning of the human epidermis and that radiation with wavelengths of from 280 to 320 nm, known as UV-B radiation, causes erythemas and skin burns which may be harmful to the development of natural tanning; this UV-B radiation must therefore be screened out from the skin.

[0007] It is also known that UV-A radiation, with wavelengths of from 320 to 400 nm, which causes browning of the skin, is capable of adversely affecting the skin, in particular in the case of sensitive skin or of skin continually exposed to solar radiation. UV-A rays cause, in particular, a loss in the elasticity of the skin and the appearance of wrinkles, resulting in premature aging. UV-A irradiation promotes the triggering of the erythemal reaction or accentuates this reaction in certain individuals and can even be the cause of phototoxic or photoallergic reactions. It is therefore also desirable to screen out UV-A radiation.

[0008] A wide variety of cosmetic/dermatological compositions suited for the photoprotection (UV-A and/or UV-B) of the skin are known to this art.

[0009] These antisun/sunscreen compositions are typically emulsions of oil-in-water type (namely, a cosmetically acceptable vehicle composed of a continuous aqueous dispersing phase and of a noncontinuous oily dispersed phase) which comprise, at various concentrations, one or more conventional, lipophilic and/or hydrophilic, organic screening agents capable of selectively absorbing harmful UV radiation, these screening agents (and their amounts) being selected according to the sun protection factor desired, the sun protection factor (SPF) being expressed mathematically by the ratio of the dose of UV radiation necessary to reach the erythemogenic threshold with the UV screening agent to the dose of UV radiation necessary to reach the erythemogenic threshold without UV screening agent.

[0010] Antisun/sunscreen compositions based on amino-substituted 2-hydroxybenzophenone derivatives are described in EP-1,046,391. These compounds screen out UV-A radiation.

SUMMARY OF THE INVENTION

[0011] It has now surprisingly and unexpectedly been determined that the combination or intimate immixture of two specific known sunscreens permits formulating, due to a notable synergistic effect, antisun/sunscreen compositions exhibiting protection factors which are markedly improved and in any event much higher than those which can be obtained utilizing either of the screening agents alone.

[0012] Thus, the present invention features novel topically applicable cosmetic or dermatological compositions, comprising (a) 0.1% to 15% by weight, with respect to the total weight of the composition, of benzene-1,4-di(3-methylidene-10-camphorsulfonic acid), optionally in the partially or completely neutralized state, as a first screening agent, and (b) 0.1% to 15% by weight, with respect to the total weight of the composition, of at least one amino-substituted 2-hydroxybenzophenone compound of formula (I) as defined below, as a second screening agent, formulated into a topically applicable, cosmetically/dermatologically acceptable vehicle, diluent or carrier therefor. The said first and second screening agents are present in the compositions according to the invention in a proportion or in such amounts that provide synergistic results with regard to the sun protection factors conferred.

[0013] The present invention also features a regime or regimen for the UV-photoprotection of human skin and/or hair against the deleterious effects of ultraviolet radiation, in particular solar radiation.

[0014] This invention also features formulating an amino-substituted 2-hydroxybenzophenone compound of formula (I) into cosmetic or dermatological compositions suited for the protection of the skin and/or hair against ultraviolet radiation, in particular solar radiation, such compositions comprising at least benzene-1,4-di(3-methylidene-10-camphorsulfonic acid), optionally in the partially or completely neutralized form, for the purpose of eliciting a synergistic effect with regard to the sun protection factors conferred.

DETAILED DESCRIPTION OF BEST MODE AND SPECIFIC/PREFERRED EMBODIMENTS OF THE INVENTION

[0015] More particularly according to the present invention, benzene-1,4-di(3-methylidene-10-camphorsulfonic acid) and its various salts, described in particular in FR-A-2,528,420 and FR-A-2,639,347, are UV-screening agents already known per se (“broad spectrum” screening agents) capable in fact of absorbing ultraviolet rays with wavelengths of from 280 to 400 nm, with absorption maxima of from 320 to 400 nm, in particular in the vicinity of 345 nm. These UV-screening agents have the following structural formula (II):

[0016] in which B is a hydrogen atom, an alkali metal, an NH(R)⁺ ₃ radical in which the radicals R, which may be identical or different, are each a hydrogen atom or a C₁-C₄ alkyl or hydroxyalkyl radical, or an M^(p+)/p group, wherein M^(p+) is a polyvalent metal cation in which p is equal to 2 or 3 or 4, M^(p+) preferably having a metal cation selected from among Ca²⁺, Zn²⁺, Mg²⁺, Ba²⁺, Al³⁺ and Zr⁴⁺. It will be appreciated that the compounds of formula (II) above comprehend the “cis-trans” isomer about one or more double bond(s) and that all such isomers are within the scope of the present invention.

[0017] The benzene-1,4-di(3-methylidene-10-camphorsulfonic acid) and the various salts thereof are preferably present in the compositions of the invention in proportions ranging from 1% to 10% by weight and more preferably from 2% to 8% by weight with respect to the total weight of the composition.

[0018] The amino-substituted 2-hydroxybenzophenone compounds in accordance with the invention have the following structural formula (I):

[0019] in which R¹ and R², which may be identical or different, are each a hydrogen atom, a C₁-C₂₀ alkyl radical, a C₂-C₁₀ alkenyl radical, a C₃-C₁₀ cycloalkyl radical or a C₃-C₁₀ cycloalkenyl radical, with the proviso that R¹ and R² can together form, with the nitrogen atom to which they are bonded, a 5- or 6-membered heterocyclic ring member; R³ and R⁴, which may be identical or different, are each a C₁-C₂₀ alkyl radical, a C₂-C₁₀ alkenyl radical, a C₃-C₁₀ cycloalkyl radical, a C₃-C₁₀ cycloalkenyl radical, a C₁-C₁₂ alkoxy radical, a (C₁-C₂₀) alkoxycarbonyl radical, a C₁-C₁₂ alkylamino radical, a di(C₁-C₁₂) alkylamino radical, an aryl radical or a heteroaryl radical which is optionally substituted, or a water-solubilizing substituent selected from among a carboxylate group, a sulfonate group or an ammonium residue; X is a hydrogen atom or a —COOR⁵ or —CONR⁶R⁷ radical; R⁵, R⁶ and R⁷, which may be identical or different, are each a hydrogen atom, a C₁-C₂₀ alkyl radical, a C₂-C₁₀ alkenyl radical, a C₃-C₁₀ cycloalkyl radical, a C₃-C₁₀ cycloalkenyl radical, a —(YO)_(o)-Z radical or an aryl radical; Y is —(CH₂)₂—, —(CH₂)₃—, —(CH₂)₄— or —CH—CH₃—CH₂—; Z is —CH₂—CH₃, —CH₂CH₂CH₃, —CH₂—CH₂—CH₂—CH₃ or —CH(CH₃)—CH₃; m is an integer ranging from 0 to 3; n is an integer ranging from 0 to 3; o is an integer ranging from 1 to 2.

[0020] Representative C₁-C₂₀ alkyl radicals include, for example: methyl, ethyl, n-propyl, 1-methylethyl, n-butyl, 1-methylpropyl, 2-methylpropyl, 1,1-dimethyl-ethyl, n-pentyl, 1-methylbutyl, 2-methylbutyl, 3-methyl-butyl, 2,2-dimethylpropyl, 1-ethylpropyl, n-hexyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 1,1-dimethylbutyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl, 2,2-dimethylbutyl, 2,3-dimethylbutyl, 3,3-dimethylbutyl, 1-ethylbutyl, 2-ethylbutyl, 1,2,2-trimethylpropyl, 1-ethyl-1-methylpropyl, 1-ethyl-2-methylpropyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-nonadecyl or n-icosyl.

[0021] Representative C₂-C₁₀ alkenyl radicals include, for example: vinyl, n-propenyl, isopropenyl, 1-butenyl, 2-butenyl, 1-pentenyl, 2-pentenyl, 2-methyl-1-butenyl, 2-methyl-2-butenyl, 3-methyl-1-butenyl, 1-hexenyl, 2-hexenyl, 1-heptenyl, 2-heptenyl, 1-octenyl or 2-octenyl.

[0022] Representative C₁-C₁₂ alkoxy radicals include, for example: methoxy, ethoxy, n-propoxy, n-butoxy, n-pentoxy, 1-methylpropoxy, 3-methylbutoxy, 2,2-dimethylpropoxy, 1-methyl-1-ethylpropoxy, octoxy, 2-methylpropoxy, 1,1-dimethylpropoxy, hexoxy, heptoxy or 2-ethylhexoxy.

[0023] Representative C₃-C₁₀ cycloalkyl radicals include, for example: cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, 1-methylcyclo-propyl, 1-ethylcyclopropyl, 1-propylcyclopropyl, 1-butylcyclopropyl, 1-pentylcyclopropyl, 1-methyl-1-butylcyclopropyl, 1,2-dimethylcyclopropyl, 1-methyl-2-ethylcyclopropyl, cyclooctyl, cyclononyl or cyclodecyl.

[0024] And representative C₃-C₁₀ cycloalkenyl radicals having one or more double bonds include, for example: cyclopropenyl, cyclobutenyl, cyclopentenyl, cyclopentadienyl, cyclohexenyl, 1,3-cyclohexadienyl, 1,4-cyclohexadienyl, cycloheptenyl, cycloheptatrienyl, cyclooctenyl, 1,5-cyclooctadienyl, cyclooctatetraenyl, cyclononenyl or cyclodecenyl.

[0025] The cycloalkyl or cycloalkenyl radicals can be substituted by one or more substituents (preferably from 1 to 3) selected for example, from among halogen, such as chlorine, fluorine or bromine; cyano; nitro; amino; C₁-C₄ alkylamino; di(C₁-C₄) alkylamino; C₁-C₄ alkyl; C₁-C₄ alkoxy; or hydroxyl. They can also contain from 1 to 3 heteroatoms, such as sulfur, oxygen or nitrogen, the free valencies of which can be satisfied by a hydrogen atom or a C₁-C₄ alkyl radical.

[0026] The aryl radicals are preferably phenyl or naphthyl which can be substituted by one or more substituents (preferably from 1 to 3) selected, for example, from among halogen, such as chlorine, fluorine or bromine; cyano; nitro; amino; C₁-C₄ alkylamino; di(C₁-C₄)alkylamino; C₁-C₄ alkyl; C₁-C₄ alkoxy; or hydroxyl. Phenyl, methoxyphenyl and naphthyl are the preferred.

[0027] The heteroaryl radicals generally contain one or more heteroatoms selected from among sulfur, oxygen or nitrogen.

[0028] The water-solubilizing groups are, for example, carboxylate or sulfonate groups and, more particularly, their salts with physiologically acceptable cations, such as alkali metal salts or trialkylammonium salts, such as tri(hydroxyalkyl)-ammonium or 2-methylpropan-1-ol-2-ammonium salts. Also exemplary are the ammonium groups, such as alkylammoniums, and their salified forms with physiologically acceptable anions.

[0029] And exemplary 5- or 6-membered heterocyclic ring members formed by the R¹ and R² radicals with the nitrogen atom, are pyrrolidone or piperidine.

[0030] The amino groups can be bonded to the benzene ring in the ortho, meta or para position with respect to the carbonyl radical and more preferably in the para position.

[0031] One family of preferred compounds of formula (I) is that having the following structural formula (Ia):

[0032] in which R¹ and R², which may be identical or different, are each a hydrogen atom or a C₁-C₁₂ alkyl radical, or together form, with the nitrogen atom to which they are bonded, a 5- or 6-membered heterocyclic ring member; X is —COOR⁵ or —CONR⁶ R⁷; R⁵ is a hydrogen atom, a C₁-C₁₂ alkyl radical, or a C₃-C₆ cycloalkyl radical; and R⁶ and R⁷, which may be identical or different, are each a hydrogen atom, a C₁-C₁₂ alkyl radical, or a C₅-C₆ cycloalkyl radical.

[0033] The more particularly preferred compounds of formula (Ia) are those in which: R¹ and R², which may be identical or different, are each a C₁-C₄ alkyl radical and more particularly ethyl; R⁵ is a C₃-C₈ alkyl radical; R⁶ and R⁷, which may be identical or different, are each a C₁-C₈ alkyl radical.

[0034] Another family of preferred compounds of formula (I) comprises those having the following structural formula (Ib):

[0035] in which R¹ and R², which may be identical or different, are each a C¹-C¹² alkyl radical, or together form, with the nitrogen atom to which they are bonded, a 5- or 6-membered heterocyclic ring member.

[0036] Particularly preferred compounds of formula (Ib) are:

[0037] 4-diethylamino-2-hydroxyphenyl phenyl ketone,

[0038] 4-pyrrolidino-2-hydroxyphenyl phenyl ketone.

[0039] Another family of more particularly preferred compounds of formula (I) comprises those having the following structural formula (Ic):

[0040] in which R¹ and R², which may be identical or different, are each a hydrogen atom, or a C₁-C₈ alkyl radical, or together form, with the nitrogen atom to which they are bonded, a 5- or 6-membered heterocyclic ring member; and R⁵ is a hydrogen atom, a C₁-C₁₂ alkyl radical, or a C₃-C₆ cycloalkyl radical.

[0041] Exemplary compounds of formula (Ic) include:

[0042] 2-(4-pyrrolidino-2-hydroxybenzoyl)benzoic acid,

[0043] methyl 2-(4-diethylamino-2-hydroxybenzoyl)benzoate,

[0044] 2-ethylhexyl 2-(4-diethylamino-2-hydroxybenzoyl)-benzoate,

[0045] cyclohexyl 2-(4-diethylamino-2-hydroxybenzoyl)-benzoate,

[0046] n-hexyl 2-(4-diethylamino-2-hydroxybenzoyl)benzoate,

[0047] 2-(4-dibutylamino-2-hydroxybenzoyl)benzoic acid,

[0048] methyl 2-(4-dibutylamino-2-hydroxybenzoyl)benzoate, and

[0049] isobutyl 2-(4-dibutylamino-2-hydroxybenzoyl)benzoate.

[0050] A very particularly preferred compound of formula (I) is n-hexyl 2-(4-diethylamino-2-hydroxy-benzoyl) benzoate.

[0051] The compounds of formula (I) as described above are known per se and their structures and syntheses thereof are described in EP-A-1,046,391 and DE-100 12 408, hereby expressly incorporated by reference.

[0052] The amino-substituted 2-hydroxybenzophenone compounds according to this invention are preferably present in the compositions of the invention in proportions more preferably ranging from 1% to 10% by weight and more particularly from 2% to 8% by weight with respect to the total weight of the composition.

[0053] The compositions according to this invention can additionally comprise at least one organic photoprotective agent and/or at least one inorganic photoprotective agent which are active in the UV-A and/or UV-B regions (absorbers), such photoprotective agents being water-soluble, fat-soluble or insoluble in commonly used cosmetic solvents.

[0054] The organic UV-photoprotective agents are selected, in particular, from among the anthranilates; cinnamic derivatives; dibenzoylmethane derivatives; salicylic derivatives; camphor derivatives, other than the compound (II); triazine derivatives, such as those described in U.S. Pat. Nos. 4,367,390 and 4,724,137, EP-863,145, EP-517,104, EP-570,838, EP-796,851, EP-775,698, EP-878,469, EP-933,376, EP-507,691, EP-507,692, EP-790,243 and EP-944,624; benzophenone derivatives, other than those of formula (I); β,β-diphenylacrylate derivatives; benzotriazole derivatives; benzalmalonate derivatives; benzimidazole derivatives; imidazolines; bisbenzoazolyl derivatives as described in EP-669,323 and U.S. Pat. No. 2,463,264; p-aminobenzoic acid (PABA) derivatives; methylenebis(hydroxyphenylbenzotriazole) derivatives as described in U.S. Pat. Nos. 5,237,071 and 5,166,355, GB-2,303,546, DE-197 26 184 and EP-893,119; screening polymers and screening silicones, such as those described, in particular, in WO-93/04665; dimers derived from β-alkylstyrene, such as those described in DE-198 55 649; 4,4-diarylbutadienes as described in EP-0,967,200 and DE-197 55 649, and mixtures thereof.

[0055] Exemplary organic photoprotective agents which are active in the UV-A and/or UV-B regions are indicated below under their INCI names:

[0056] para-Aminobenzoic acid derivatives:

[0057] PABA,

[0058] Ethyl PABA,

[0059] Ethyl Dihydroxypropyl PABA,

[0060] Ethylhexyl Dimethyl PABA, marketed, in particular, under the trademark “Escalol 507” by ISP,

[0061] Glyceryl PABA,

[0062] PEG-25 PABA, marketed under the trademark “Uvinul P25” by BASF,

[0063] Salicylic derivatives:

[0064] Homosalate, marketed under the trademark “Eusolex HMS” by Rona/EM Industries,

[0065] Ethylhexyl Salicylate, marketed under the trademark “Neo Heliopan OS” by Haarmann and Reimer,

[0066] Dipropyleneglycol Salicylate, marketed under the trademark “Dipsal” by Scher,

[0067] TEA Salicylate, marketed under the trademark “Neo Heliopan TS” by Haarmann and Reimer,

[0068] Dibenzoylmethane derivatives:

[0069] Butyl Methoxydibenzoylmethane, marketed, in particular, under the trademark “Parsol 1789” by Hoffmann-LaRoche, Isopropyl Dibenzoylmethane,

[0070] Isopropyl Dibenzoylmethane,

[0071] Cinnamic derivatives:

[0072] Ethylhexyl Methoxycinnamate, marketed, in particular, under the trademark “Parsol MCX” by Hoffmann-LaRoche,

[0073] Isopropyl Methoxy cinnamate,

[0074] Isoamyl Methoxy cinnamate, marketed under the trademark “Neo Heliopan E 1000” by Haarmann and Reimer,

[0075] Cinoxate,

[0076] DEA Methoxycinnamate,

[0077] Diisopropyl Methylcinnamate,

[0078] Glyceryl Ethylhexanoate Dimethoxycinnamate,

[0079] β,β-Diphenylacrylate derivatives:

[0080] Octocrylene, marketed, in particular, under the trademark “Uvinul N539” by BASF,

[0081] Etocrylene, sold marketed, in particular, under the trademark “Uvinul N35” by BASF,

[0082] Benzophenone derivatives:

[0083] Benzophenone-1, marketed under the trademark “Uvinul 400” by BASF,

[0084] Benzophenone-2, marketed under the trademark “Uvinul D50” by BASF,

[0085] Benzophenone-3 or Oxybenzone, marketed under the trademark “Uvinul M40” by BASF,

[0086] Benzophenone-4, marketed under the trademark “Uvinul MS40” by BASF,

[0087] Benzophenone-5,

[0088] Benzophenone-6, marketed under the trademark “Helisorb 11” by Norquay,

[0089] Benzophenone-8, marketed under the trademark “Spectra-Sorb UV-24” by American Cyanamid,

[0090] Benzophenone-9, marketed under the trademark “Uvinul DS-49” by BASF,

[0091] Benzophenone-12,

[0092] Benzylidenecamphor derivatives:

[0093] 3-Benzylidene camphor, marketed under the trademark “Mexoryl SD” by Chimex,

[0094] 4-Methylbenzylidene camphor, marketed under the trademark “Eusolex 6300” by Merck,

[0095] Benzylidene Camphor Sulfonic Acid, marketed under the trademark “Mexoryl SL” by Chimex,

[0096] Camphor Benzalkonium Methosulfate, marketed under the trademark “Mexoryl SO” by Chimex,

[0097] Polyacrylamidomethyl Benzylidene Camphor, marketed under the trademark “Mexoryl SW” by Chimex,

[0098] Phenylbenzimidazole derivatives:

[0099] Phenylbenzimidazole Sulfonic Acid, marketed, in particular, under the trademark “Eusolex 232” by Merck,

[0100] Disodium Phenyl Dibenzimidazole Tetrasulfonate marketed under the trademark “Neo Heliopan AP” by Haarmann and Reimer,

[0101] Triazine derivatives:

[0102] Anisotriazine, marketed under the trademark “Tinosorb S” by Ciba Specialty Chemicals,

[0103] Ethylhexyl triazone, marketed, in particular, under the trademark “Uvinul T150” by BASF,

[0104] Diethylhexyl Butamido Triazone, marketed under the trademark “Uvasorb HEB” by Sigma 3V,

[0105] 2,4,6-tris(diisobutyl 4′-aminobenzalmalonate)-s-triazine,

[0106] Phenylbenzotriazole derivatives:

[0107] Drometrizole Trisiloxane, marketed under the trademark “Silatrizole” by Rhodia Chimie,

[0108] Methylenebis(benzotriazolyltetramethylbutylphenol), marketed in the solid form under the trademark “Mixxim BB/100” by Fairmount Chemical or in the micronized form in aqueous dispersion under the trademark “Tinosorb M” by Ciba Specialty Chemicals,

[0109] Anthranilic derivatives:

[0110] Menthyl anthranilate, marketed under the trademark “Neo Heliopan MA” by Haarmann and Reimer,

[0111] Imidazoline derivatives:

[0112] Ethylhexyl Dimethoxybenzylidene Dioxoimidazoline Propionate,

[0113] Benzalmalonate derivatives:

[0114] Polyorganosiloxane comprising benzalmalonate functional group, marketed under the trademark “Parsol SLX” by Hoffmann-LaRoche, and mixtures thereof.

[0115] The organic UV-photoprotective agents which are more particularly preferred are selected from among the following compounds:

[0116] Ethylhexyl Salicylate,

[0117] Butyl Methoxydibenzoylmethane,

[0118] Ethylhexyl Methoxycinnamate,

[0119] Octocrylene,

[0120] Phenylbenzimidazole Sulfonic Acid,

[0121] Benzophenone-3,

[0122] Benzophenone-4,

[0123] Benzophenone-5,

[0124] 4-Methylbenzylidene Camphor,

[0125] Benzimidazilate,

[0126] Disodium Phenyl Dibenzimidazole Tetrasulfonate,

[0127] Anisotriazine,

[0128] Ethylhexyl triazone,

[0129] Diethylhexyl Butamido Triazone,

[0130] Methylenebis(benzotriazolyltetramethylbutylphenol),

[0131] Drometrizole Trisiloxane,

[0132] 2,4,6-Tris(diisobutyl 4′-aminobenzalmalonate)-s-triazine, and mixtures thereof.

[0133] The inorganic UV-photoprotective agents are typically selected from among pigments or alternatively nanopigments (mean size of the primary particles: generally ranging from 5 nm to 100 nm, preferably from 10 nm to 50 nm) formed from coated or uncoated metal oxides, such as, for example, nanopigments formed from titanium dioxide (amorphous or crystallized in the rutile and/or anatase form), iron oxide, zinc oxide, zirconium oxide or cerium oxide, and mixtures thereof. Conventional coating agents are, furthermore, alumina and/or aluminum stearate. Such coated or uncoated metal oxide nanopigments are described, in particular, in EP-518,772 and EP-518,773.

[0134] The compositions according to the invention can also comprise agents for the artificial tanning and/or browning of the skin (self-tanning or artificial/sunless tanning agents), such as, for example, dihydroxyacetone (DHA).

[0135] The compositions in accordance with the present invention can additionally comprise conventional cosmetic additives and adjuvants selected, in particular, from among fatty substances, organic solvents, ionic or nonionic thickeners, softeners, antioxidants, agents for combating free radicals, opacifiers, stabilizers, emollients, silicones, α-hydroxy acids, antifoaming agents, moisturizing agents, vitamins, insect repellents, substance P antagonists, anti-inflammatories, fragrances, preservatives, surfactants, fillers, polymers, propellants, basifying or acidifying agents, colorants or any other ingredient commonly used in the cosmetic and/or dermatological field, in particular for the production of self-tanning compositions in the form of emulsions.

[0136] The fatty substances can be an oil or a wax, or mixture thereof. By the term “oil” is intended a compound which is liquid at ambient temperature. By the term “wax” is intended a compound which is solid or substantially solid at ambient temperature and for which the melting point is generally greater than 35° C.

[0137] Exemplary oils are mineral oils (liquid paraffin); vegetable oils (sweet almond, macadamia, blackcurrant seed or jojoba oil); synthetic oils, such as perhydrosqualene, fatty alcohols, acids or esters (such as the C₁₂-C₁₅ alkyl benzoate marketed under the trademark “Finsolv TN” by Finetex, octyl palmitate, isopropyl lanolate or triglycerides, including those of capric/caprylic acids), or oxyethylenated or oxypropylenated fatty esters and ethers; silicone oils (cyclomethicone, polydimethylsiloxanes or PDMS); fluorinated oils; polyalkylenes and their mixtures.

[0138] Exemplary waxy compounds are paraffin wax, carnauba wax, beeswax or hydrogenated castor oil.

[0139] And exemplary organic solvents include the lower alcohols and polyols having at most 8 carbon atoms.

[0140] The thickeners are advantageously selected, in particular, from among the crosslinked polyacrylic acids or modified or unmodified guar gums and celluloses, such as hydroxypropylated guar gum, methylhydroxyethylcellulose and hydroxypropylmethylcellulose.

[0141] Of course, one skilled in this art will take care to select the abovementioned optional additional compound or compounds and/or their amounts such that the advantageous properties, in particular the synergistic effect, intrinsically associated with the combination in accordance with the invention are not, or not substantially, detrimentally affected by the envisaged addition or additions.

[0142] The compositions according to the invention can be formulated according to techniques well known to this art, in particular those suited for the preparation of emulsions of oil-in-water or water-in-oil type.

[0143] These compositions can be provided, in particular, in the form of a simple or complex emulsion (O/W, W/O, O/W/O or W/O/W), such as a cream or a milk, or in the form of a gel or of a cream gel, or in the form of a lotion, of a powder or of a solid tube and can optionally be packaged as an aerosol and provided in the form of a foam or spray.

[0144] The compositions according to the invention are preferably formulated an oil-in-water or water-in-oil emulsion.

[0145] When an emulsion, the aqueous phase thereof can comprise a nonionic vesicular dispersion, prepared according to known processes (Bangham, Standish and Watkins, J. Mol. Biol., 13 238 (1965), FR-2,315,991 and FR-2,416,008).

[0146] The cosmetic compositions of the invention are useful in a regime or regimen for protecting the human epidermis or the hair against ultraviolet irradiation, as an antisun/sunscreen composition or as a makeup product.

[0147] When the cosmetic compositions according to the invention are used for the protection of the human epidermis against UV rays or as an antisun/sunless composition, they can be provided in the form of a suspension or dispersion in solvents or fatty substances, in the form of a nonionic vesicular dispersion or in the form of an emulsion, preferably of oil-in-water type, such as a cream or a milk, in the form of an ointment, gel, cream gel, solid tube, powder, stick, aerosol foam or spray.

[0148] When the cosmetic compositions according to the invention are used for the protection of the hair against UV rays, they can be provided in the form of a shampoo, lotion, gel, emulsion or nonionic vesicular dispersion and can constitute, for example, a rinse-out composition, to be applied before or after shampooing, before or after dyeing or bleaching, and before, during or after perming or hair straightening, a styling or treating lotion or a styling or treating gel, a lotion or a gel for blow-drying or hair setting, or a composition for perming or straightening, dyeing or bleaching the hair.

[0149] When the compositions are used as a product for making up the eyelashes, eyebrows or skin, such as a treatment cream for the epidermis, foundation, lipstick, eyeshadow, face powder, mascara or eyeliner, it can be provided in the anhydrous or aqueous, pasty or solid form, such as oil-in-water or water-in-oil emulsions, nonionic vesicular dispersions, or suspensions.

[0150] For purposes of illustration, for the antisun/sunscreen formulations in accordance with the invention which contain a vehicle of oil-in-water emulsion type, the aqueous phase (comprising in particular the hydrophilic UV-screening agents) generally constitutes from 50% to 95% by weight, preferably from 70% to 90% by weight, with respect to the entire formulation, the oily phase (comprising in particular the lipophilic UV-screening agents) from 5% to 50% by weight, preferably from 10% to 30% by weight, with respect to the entire formulation, and the (co)emulsifier(s) from 0.5% to 20% by weight, preferably from 2% to 10% by weight, with respect to the total weight of the formulation.

[0151] In order to further illustrate the present invention and the advantages thereof, the following specific examples are given, it being understood that same are intended only as illustrative and in nowise limitative.

EXAMPLE 1

[0152] The following specific composition according to the present invention was formulated via simple intimate admixing of the several constituents thereof: 80/20 Mixture of cetearyl alcohol and of 7 g oxyethylenated (33 EO) cetearyl alcohol (Sinnowax AO, Henkel) Mixture of glycerol mono- and distearate 2 g (Cerasynt SD-V. ISP) Cetyl alcohol 1.5 g Polydimethylsiloxane (Dow Corning 200 Fluid, 1 g Dow Corning) C₁₂-C₁₅ Alkyl benzoate (Witconol TN, Witco) 10 g 2-(4-Diethylamino-2-hydroxybenzoyl)benzoic 2 g acid hexyl ester Glycerol 10 g Terephthalylidene Dicamphor Sulfonic Acid 2 g (Mexoryl SX, Chimex) Triethanolamine q.s. pH 7 Preservatives q.s. Demineralized water q.s. for 100 g

EXAMPLE 2

[0153] The following specific composition according to the present invention was formulated via simple intimate admixing of the several constituents thereof: Glycerol mono/distearate/polyethylene glycol 2 g (100 EO) stearate mixture (Arlacel 165 FL, ICI) Stearyl alcohol (Lanette 18, Henkel) 1 g Palm oil stearic acid (Stéarine TP, Stéarinerie Dubois) 2.5 g Polydimethylsiloxane (Dow Corning 200 Fluid, 0.5 g Dow Corning) C₁₂/C₁₅ Alkyl benzoate (Witconol TN, Witco) 15 g Triethanolamine 0.5 g 2-(4-Diethylamino-2-hydroxybenzoyl)benzoic 2.5 g acid hexyl ester Glycerol 5 g Hexadecyl phosphate, potassium salt 1 g (Amphisol K, Hoffmann-LaRoche) Polyacrylic acid (Synthalen K, 3V) 0.3 g Hydroxypropyl methyl cellulose 0.1 g (Methocel F4M, Dow Chemical) Terephthalylidene Dicamphor Sulfonic Acid 1.5 g (Mexoryl SX, Chimex) Triethanolamine q.s. pH 7 Preservatives q.s. Demineralized water q.s. for 100 g

[0154] Each patent, patent application and literature article/report cited or indicated herein is hereby expressly incorporated by reference.

[0155] While the invention has been described in terms of various specific and preferred embodiments, the skilled artisan will appreciate that various modifications, substitutions, omissions, and changes may be made without departing from the spirit thereof. Accordingly, it is intended that the scope of the present invention be limited solely by the scope of the following claims, including equivalents thereof. 

What is claimed is:
 1. A topically applicable cosmetic/dermatological sunscreen composition suited for the UV-photoprotection of human skin and/or hair, comprising synergistically SPF-enhancing amounts of (a) benzene-1,4-di(3-methylidene-10-camphorsulfonic acid), optionally in partially or completely neutralized state, and (b) at least one amino-substituted 2-hydroxybenzophenone compound having the following structural formula (I):

in which R¹ and R², which may be identical or different, are each a hydrogen atom, a C₁-C₂₀ alkyl radical, a C₂-C₁₀ alkenyl radical, a C₃-C₁₀ cycloalkyl radical or a C₃-C₁₀ cycloalkenyl radical, with the proviso that R¹ and R² can together form, with the nitrogen atom to which they are bonded, a 5- or 6-membered heterocyclic ring member; R³ and R⁴, which may be identical or different, are each a C₁-C₂₀ alkyl radical, a C₂-C₁₀ alkenyl radical, a C₃-C₁₀ cycloalkyl radical, a C₃-C₁₀ cycloalkenyl radical, a C₁-C₁₂ alkoxy radical, a (C₁-C₂₀) alkoxycarbonyl radical, a C₁-C₁₂ alkylamino radical, a di(C₁-C₁₂) alkylamino radical, an aryl radical or a heteroaryl radical which is optionally substituted, or a water-solubilizing substituent selected from among a carboxylate group, a sulfonate group or an ammonium residue; X is a hydrogen atom or a —COOR⁵ or —CONR⁶R⁷ radical; R⁵, R⁶ and R⁷, which may be identical or different, are each a hydrogen atom, a C₁-C₂₀ alkyl radical, a C₂-C₁₀ alkenyl radical, a C₃-C₁₀ cycloalkyl radical, a C₃-C₁₀ cycloalkenyl radical, a —(YO)_(o)-Z radical or an aryl radical; Y is —(CH₂)₂—, —(CH₂)₃—, —(CH₂)₄— or —CH—CH₃—CH₂—; Z is —CH₂—CH₃, —CH₂CH₂CH₃, —CH₂—CH₂—CH₂-CH₃ or —CH(CH₃)—CH₃; m is an integer ranging from 0 to 3; n is an integer ranging from 0 to 3; o is an integer ranging from 1 to 2, formulated into (c) a topically applicable, cosmetically/dermatologically acceptable vehicle, diluent or carrier therefor.
 2. The cosmetic/dermatological sunscreen composition as defined by claim 1, said at least one benzophenone compound (I) having the following structural formula (Ia):

in which R¹ and R², which may be identical or different, are each a hydrogen atom or a C₁-C₁₂ alkyl radical, or together form, with the nitrogen atom to which they are bonded, a 5- or 6-membered heterocyclic ring member; X is COOR⁵ or CONR⁶ R⁷; R⁵ is a hydrogen atom, a C₁-C₁₂ alkyl radical or a C₃-C₆ cycloalkyl radical; and R⁶ and R⁷, which may be identical or different, are each a hydrogen atom, a C₁-C₁₂ alkyl radical or a C₅-C₆ cycloalkyl radical.
 3. The cosmetic/dermatological sunscreen composition as defined by claim 2, wherein formula (Ia), R¹ and R², which may be identical or different, are each a C₁-C₄ alkyl radical; R⁵ is a C₃-C₈ alkyl radical; and R⁶ and R⁷, which may be identical or different, are each a C₁-C₈ alkyl radical.
 4. The cosmetic/dermatological sunscreen composition as defined by claim 1, said at least one benzophenone compound (I) having the following structural formula (Ib):

in which R¹ and R², which may be identical or different, are each a C₁-C₁₂ alkyl radical, or together form, with the nitrogen atom to which they are bonded, a 5- or 6-membered heterocyclic ring member.
 5. The cosmetic/dermatological sunscreen composition as defined by claim 4, said at least one compound of formula (Ib) comprising 4-diethylamino-2-hydroxyphenyl phenyl ketone and/or 4-pyrrolidino-2-hydroxyphenyl phenyl ketone.
 6. The cosmetic/dermatological sunscreen composition as defined by claim 1, said at least one benzophenone compound (I) having the following structural formula (Ic):

in which R¹ and R², which may be identical or different, are each a hydrogen atom or a C₁-C₈ alkyl radical, or together form, with the nitrogen atom to which they are bonded, a 5- or 6-membered heterocyclic ring member; and R⁵ is a hydrogen atom, a C₁-C₁₂ alkyl radical or a C₃-C₆ cycloalkyl radical.
 7. The cosmetic/dermatological sunscreen composition as defined by claim 6, said at least one compound of formula (Ic) comprising 2-(4-pyrrolidino-2-hydroxybenzoyl)benzoic acid, methyl 2-(4-diethylamino-2-hydroxybenzoyl)benzoate, 2-ethylhexyl 2-(4-diethylamino-2-hydroxybenzoyl)-benzoate, cyclohexyl 2-(4-diethylamino-2-hydroxybenzoyl)-benzoate, n-hexyl 2-(4-diethylamino-2-hydroxybenzoyl)benzoate, 2-(4-dibutylamino-2-hydroxybenzoyl)benzoic acid, methyl 2-(4-dibutylamino-2-hydroxybenzoyl)benzoate, and/or isobutyl 2-(4-dibutylamino-2-hydroxybenzoyl)benzoate.
 8. The cosmetic/dermatological sunscreen composition as defined by claim 7, said at least one compound of formula (Ic) comprising n-hexyl 2-(4-diethyl-amino-2-hydroxybenzoyl)benzoate.
 9. The cosmetic/dermatological sunscreen composition as defined by claim 1, said at least one amino-substituted 2-hydroxybenzophenone compound of formula (I) comprising from 0.1% to 15% by weight with respect to the total weight thereof.
 10. The cosmetic/dermatological sunscreen composition as defined by claim 9, said at least one amino-substituted 2-hydroxybenzophenone compound of formula (I) comprising from 1% to 10% by weight with respect to the total weight thereof.
 11. The cosmetic/dermatological sunscreen composition as defined by claim 10, said at least one amino-substituted 2-hydroxybenzophenone compound of formula (I) comprising from 2% to 8% by weight with respect to the total weight thereof.
 12. The cosmetic/dermatological sunscreen composition as defined by claim 1, said camphorsulfonic acid screening agent (a) having the following structural formula (II):

in which B is a hydrogen atom, an alkali metal, an NH(R)⁺ ₃ radical wherein the R radicals, which can be identical or different, are each a hydrogen atom or a C₁-C₄ alkyl or hydroxyalkyl radical, or an M^(p+)/p group, wherein M^(p+) is a polyvalent metal cation in which p is equal to 2 or 3 or
 4. 13. The cosmetic/dermatological sunscreen composition as defined by claim 12, said benzene-1,4-di(3-methylidene-10-camphorsulfonic acid) comprising from 1% to 10% by weight with respect to the total weight thereof.
 14. The cosmetic/dermatological sunscreen composition as defined by claim 13, said benzene-1,4-di(3-methylidene-10-camphorsulfonic acid) comprising from 2% to 8% by weight with respect to the total weight thereof.
 15. The cosmetic/dermatological sunscreen composition as defined by claim 1, additionally comprising at least one other organic screening agent which is active in the UV-A and/or UV-B regions.
 16. The cosmetic/dermatological sunscreen composition as defined by claim 15, said additional organic UV screening agent or agents being selected from among anthranilates; cinnamic derivatives; salicylic derivatives; camphor derivatives, other than the compound of formula (II); triazine derivatives; benzophenone derivatives, other than those of formula (I); β,β-diphenylacrylate derivatives; benzotriazole derivatives; benzalmalonate derivatives; benzimidazole derivatives; imidazolines; bisbenzoazolyl derivatives; p-aminobenzoic acid (PABA) derivatives; methylenebis(hydroxyphenylbenzotriazole) derivatives; screening polymers and screening silicones; dimers derived from α-alkylstyrene; and 4,4-diarylbutadienes.
 17. The cosmetic/dermatological sunscreen composition as defined by claim 16, said organic UV screening agent or agents being selected from among Ethylhexyl Salicylate, Octocrylene, Ethylhexyl Methoxycinnamate, Butyl Methoxydibenzoylmethane, Phenylbenzimidazole Sulfonic Acid, Benzophenone-3, -Benzophenone-4, Benzophenone-5,4-Methylbenzylidene camphor, Disodium Phenyl Dibenzimidazole Tetrasulfonate, Anisotriazine, Ethylhexyl triazone, Diethylhexyl Butamido Triazone, 2,4,6-Tris(diisobutyl 4′-aminobenzalmalonate)-s-trizine, Drometrizole Trisiloxane, Methylenebis(benzotriazolyltetramethylbutyl-phenol), and mixtures thereof.
 18. The cosmetic/dermatological sunscreen composition as defined by claim 1, additionally comprising coated or uncoated metal oxide pigments or nanopigments.
 19. The cosmetic/dermatological sunscreen composition as defined by claim 18, said pigments or nanopigments comprising coated or uncoated titanium dioxide, zinc oxide, iron oxide, zirconium oxide or cerium oxide, and mixtures thereof.
 20. The cosmetic/dermatological sunscreen composition as defined by claim 1, additionally comprising at least one agent for the artificial tanning and/or browning of the skin.
 21. The cosmetic/dermatological sunscreen composition as defined by claim 1, additionally comprising at least one adjuvant or additive selected from among fatty substances, organic solvents, ionic or nonionic thickeners, softeners, antioxidants, agents for combating free radicals, opacifiers, stabilizers, emollients, silicones, α-hydroxy acids, antifoaming agents, moisturizing agents, vitamins, insect repellents, fragrances, preservatives, surfactants, anti-inflammatories, substance P antagonists, fillers, polymers, propellants, basifying or acidifying agents, or colorants.
 22. The cosmetic/dermatological sunscreen composition as defined by claim 1, formulated as a nonionic vesicular dispersion, an O/W or W/O emulsion, a cream, a milk, a gel, a cream gel, a suspension, a dispersion, a powder, a solid tube, a foam or a spray.
 23. The cosmetic/dermatological sunscreen composition as defined by claim 1, formulated as a makeup for the eyelashes, eyebrows or skin and provided in the anhydrous or aqueous, pasty or solid form, in the form of an emulsion, of a suspension or of a dispersion.
 24. The cosmetic/dermatological sunscreen composition as defined by claim 1, formulated for the protection of the hair against ultraviolet rays and provided in the form of a shampoo, of a lotion, of a gel, of an emulsion, or of a nonionic vesicular dispersion.
 25. A regime or regimen for photoprotecting human skin and/or hair against the deleterious effects of ultraviolet irradiation, comprising topically applying thereon an effective amount of a cosmetic/dermatological sunscreen composition comprising synergistically SPF-enhancing amounts of (a) benzene-1,4-di(3-methylidene-10-camphorsulfonic acid), optionally in partially or completely neutralized state, and (b) at least one amino-substituted 2-hydroxybenzophenone compound having the following structural formula (I):

in which R¹ and R², which may be identical or different, are each a hydrogen atom, a C₁-C₂₀ alkyl radical, a C₂-C₁₀ alkenyl radical, a C₃-C₁₀ cycloalkyl radical or a C₃-C₁₀ cycloalkenyl radical, with the proviso that R¹ and R² can together form, with the nitrogen atom to which they are bonded, a 5- or 6-membered heterocyclic ring member; R³ and R⁴, which may be identical or different, are each a C₁-C₂₀ alkyl radical, a C₂-C₁₀ alkenyl radical, a C₃-C₁₀ cycloalkyl radical, a C₃-C₁₀ cycloalkenyl radical, a C₁-C₁₂ alkoxy radical, a (C₁-C₂₀) alkoxycarbonyl radical, a C₁-C₁₂ alkylamino radical, a di(C₁-C₁₂) alkylamino radical, an aryl radical or a heteroaryl radical which is optionally substituted, or a water-solubilizing substituent selected from among a carboxylate group, a sulfonate group or an ammonium residue; X is a hydrogen atom or a —COOR⁵ or —CONR⁶R⁷ radical; R⁵, R⁶ and R⁷, which may be identical or different, are each a hydrogen atom, a C₁-C₂₀ alkyl radical, a C₂-C₁₀ alkenyl radical, a C₃-C₁₀ cycloalkyl radical, a C₃-C₁₀ cycloalkenyl radical, a —(YO)_(o)-Z radical or an aryl radical; Y is —(CH₂)₂—, —(CH₂)₃—, —(CH₂)₄— or —CH—CH₃—CH₂—; Z is —CH₂—CH₃, —CH₂CH₂CH₃, —CH₂—CH₂—CH₂—CH₃ or —CH(CH₃)—CH₃; m is an integer ranging from 0 to 3; n is an integer ranging from 0 to 3; o is an integer ranging from 1 to 2, formulated into (c) a topically applicable, cosmetically/dermatologically acceptable vehicle, diluent or carrier therefor.
 26. A method for synergistically enhancing the SPF of benzene-1,4-di(3-methylidene-10-camphorsulfonic acid), comprising formulating therewith an effective amount of at least one amino-substituted 2-hydroxybenzophenone compound as defined in claim
 1. 